Expansion of CD4 phenotype among CD160 receptor-expressing lymphocytes in murine pregnancy

CD160, a cell surface co-receptor, is capable of up- or downregulating cell proliferation, cytotoxicity or cytokine production on lymphocytes. Our aim was to investigate CD160⁺ lymphocytes in the periphery and at the maternal-foetal interface during murine pregnancy.

CD4⁺ , CD8⁺ and gamma/delta T-cell phenotype, TIM3 co-expression and cytotoxic activity of CD160⁺ lymphocytes of pregnant BALB/c mice were analysed by flow cytometry.

The percentage of CD160⁺ lymphocytes in the decidua was unchanged compared to non-pregnant endometrium; however, the ratio of CD4⁺ cells within the CD160 population was significantly increased. The co-expression of TIM3 co-inhibitory molecule and cytotoxicity of CD160⁺ cells were increased in the decidua.

The expansion of CD4-expressing CD160⁺ decidual lymphocytes is a new observation suggesting a potential regulatory role of T-cell function during mouse pregnancy. The altered immunological character of CD160⁺ lymphocytes could play a role in the maintenance of murine pregnancy.